PureAire Monitoring Systems, Inc.
15 |
P a g e
4: Normal Operation
The
Air Check
O
2
monitor is a single point monitor designed for the continuous detection and
measurement of ambient oxygen concentration levels.
4.1 Signal Outputs
The
Air Check
✓
O
2
monitor outputs a continuous 4-20 mA analog signal proportional to the
measured concentration of oxygen. 4 mA represents 0% O
2
and 20 mA represents 25% O
2
which is the
full range. In the event of a system fault, a specific factory defined code will be displayed on the local
digital display. This code will indicate the exact nature of the system fault. A few codes are listed
below.
CAUTION
: DO NOT connect to a powered current loop receiver. The Air Check
Oxygen monitor supplies the current loop power.
4.2 Instrument Faults
The
Air Check
✓
O
2
monitor
incorporates a number of self-checking features to
ensure reliable operation. In the event that a fault condition is detected, the
analog output signal is altered: A few common error codes are displayed in the
following table:
Condition
Analog Signal
**Supply Voltage Out of
Range Fault code 16
Analog output drops to 2 mA
Transmitter cable cut
Analog output drops to 0 mA
O
2
Cell current fault
Fault Code 128
Analog output drops to 2 mA
Fault Relay activates
O
2
System Warm Up
Analog output drops to 2 mA
Fault Relay activates and turns off when system is
in the Oxygen operation mode
O
2
Cell voltage fault
Fault Code 64
Analog output drops to 2 mA
Fault Relay activates
No Flow to the Oxygen
sensor
Fault Code 32
Analog output drops to 2 mA
Fault Relay activates
EEPROM Fault 08
Analog output drops to 2mA
NOTE:
All system faults are displayed on the front panel. Each fault has
it’own specific code to identify the specific problem. Please contact PureAire
whenever a fault is displayed.
** When using your own power supply please ensure that the voltage is
regulated to 24VDC +/- 0.5 volts. If the voltage is too low or high you will
activate a “Supply Voltage Out of Range fault and disable the monitor.
